High-capacity selective signaling system



J. C. FIELD.

HIGH CAPACITY SELECTIVE SIGNALING SYSTEM.

APPLICATION FILED 1uNE24. 1911.

1,371 ,748. Patented Mar. 15, 1921.

2 SHEETS-SHEET 1.

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' Any UNITED STATES PATENT orrlcs,

JOSEPH c. FIELD, or cannon. NEW JERSEY, ASSIGNOR, BY MESNE ASSIGNMENTS, 3T0

WESTERN ELECTRIC COMPANY, INCORPORATED, A CORPORATION OF NEW YORK.

HIGH-CAPACITY SELECTIVE SIGNALING SYSTEM.

Application filed June 24,

T 0 aZZ whom it may concern:

Be it known that I, JOSEPH C. FIELD, citizen of the United States. residing at Orange, in the county of Essex and State of New Jersey. have invented. a certain new and useful Improvement in High-Capacity Selective Signaling Systems of which the following is a full. clear. concise and exact description.

This invention relates to party lines selective signaling systems and moreparticularly to a telephone train despatching system our ploying a plurality of step-by-step selective devices adapted to be advanced in unison under control of apparatus at a sending or despatching station. each selector being adapted to close a signaling contact at some point in its movement. the position of such closure being different for each selector so that the signaling contacts at no two"stations on the same line will be closed Simultaneously. 7

In the particular class of selective systems to which this invention relates. it has been the practice heretofore to arrange all of the selectors on the line so that each will operate in response to a difierent number of current impulses from a sending station toclose its signaling contact, thus'requiring'as many operating impulses as there are'selectors on the line in order to bring about the closure of all of the signaling contacts of all of the selectors on the line. While such an ar-' rangement works satisfactorily where the number of selectors on the line is not large, the efliciency and speed with which signal ing takes place naturallydecreases as the number of selectors on one line increases and it isthe object of this invention to so arrange a system of these selectors that many more "may be operated over the same line with a given number of impulses than it has been possible to operate heretofore with the same number of impulses. 7

One of the features of this invention relates to the particular means here employed for attaining the above object and consists in' an organization of the circuits and appa-- ratus Such that the operation of selecting'a particular station on the lineis'accomplished by first Stepping all of the selectors around in unison, releasing a group of the operated selectors including the one at the selected Specification of Iletters Patent.

1911. Serial No. 635,093.

Patented Mar. 15,1921. l I

- Anotherfeature of this invention-relates I to a novel means of bringing aboutthe re-,

lease of the selectors ina certain group and consists essentially in so equipping the selectors that at a certain position in their movement a circuit will. be closed which will short-circuit holding magnets of the selectors in that roup and thus cause their" release. The various groups arearranged to be released on different numbers of impulses;

.A third feature of this invention relates to a novel means for preventlng the bells at the var ous way stations tapping onpas sing contacts and consists in so associating the bell circuit and the operative partsof the selector that said bell circuit will only be closed upon therrelease of a slow-acting holding magnet which occursupon the closure of certain contacts controlled by the selector. I

The details of apparatus and circuits are also features of this invention.

In the drawings-a Figure 1 is a circuit diagram of a Selective signaling system embodying my invention;

Fig. 2 is a detail view of the selector parts 7 and circuits in the releasing position of the selector: I Fig. 3 is a detail view of the selector parts and circuits with the signaling contact closed, and

Fig. 4. is a fragmentary detail view of the selector showing the arrangement of the con tact rings.

In Fig. l of the drawing a selective signaling system embodying this invention is shown equipped with two groups of selectors A. and B, each group including selector C, D and E with the selectors'C of each group shown in detail. The selector C of group A is shown as arranged for localbattery signaling, that of group B being arrangedfor common battery signaling, either arrange mentbeing capable otuse in a system embodying this invention. In actual practice the local signal circuits of a system will probablybe arranged to operate either all local battery orall common battery.

Located at the sending or despatching end of line wires and llis an impulse transmitter 12 comprising a rotating disk 13 provided with teeth 14: on its periphery adapted as said disk 13 rotates to close a contact 15 for completing a circuit from a local battery 16 through the winding of an impulse relay 17. The operation of the impulse relay l'l' intermittently connectsand disconnects battery 18 with the line wires 10 and 11 to op erate the selectors. Retardation coils 19, 20

and 21 connected in the line wires and a con denser 22 bridged across said line wires cooperate to smooth out the current impulses sent over the line for selecting purposes so thatYthere will be no disagreeable thump in any telephone receiver which may be bridged across the line during selection. A. non-inductive resistance 23, normally in bridge of theline wires 10 and ll through a contact'on the impulse relay 17 is intermittently disconnected from and connected therewith bygthe operation of saidimpulse relay. This non-inductive resistance 23 forms a low resistancev discharge path for the retardation coils 19,20 and 2.1 and the condenser 22 so that the current impulses over the line will not be prolonged to an e tent that will cause the sticking est-the selector magnets in case the line is of too high resistance; desi nates a des iatchers telephone set which is normally across the line wires 10 and lint the despatchers station. Theimpulse transmitter 12 may be made adjustable by means of segments 26 and;27 adjustably secured to one "face of the disk i -5 and adapted to vary the number oi teeth effective for calling purposes. i

The selectors used in: this system arealike in principle and operation and a. description ot one will suflice for all. :As shown each selector embraces a slow'actmg magnet 30 hereinafter termed a holding magnet, a quick-acting magnet 3 hereinafter termed the stepping magnet, and a ratchet wheel 32 adapted to be rotated in one direction under control of the holding. and stepping magnets 30 and 31 and returned to normalfiby' ijneans of a coiled actuating,spring 33; The hold-- ingand stepping magnets are connected in series in bridge oi the line wires and "control armaturesBet and 35respectively. Carried by the armature 3d are two angulaa'ly dis posed arms 36 and 37 the arm 36 be ng in engagement with a holdingpawl 3S and the arm 37 being in en gagementwith'a stepping pawl 39iicaari'ied bjrthe armature 35. I The movement of thearmature Bidue to euer-y gizatlon otthemagnet 30 permits thepawls 38 and 39 tohe movedinto position to engage the ratchet wheel 32 by the action of the spring-etO and 41. resp ti l Referring now to'the details otthe selector by means of which the various :teatures oit this nvention hereinbe'fore enumer :to Y normal position.

emme armature through a projecting arm 53 (see F 1g. 4t) on said spring which engages an insulating button carried by said arm. The tension of said spring being in a direction to forceit toward said armature said spring will partake of: the motion of said armature during the stepping movement thereof. A'second contact spring 54niounted adjacent to the spring 52 and in f line therewith normally bears against an insulating pin 55 on the stepping armature 35 when the selector parts are in their normal or i11 operative position and against an insulating button 56 on the outer end of the arm 37 when the holding magnet is energized and its armature 3% is in its attracted'position. As shown in the drawings the arm 51 carried by the ratchet wheel 3;.) is slightly longer.

than the arm and is locatedslightly. in advance of said arm 50. These arms are adapted to cooperate-with the contact springs '52 and in the follmring manner:

lVhen the shorter contact. arm 50 is brought into position to engage the contact spring 52 as shown in Fig. 2, it pushes the said a contact spring away from engagement with the armature 35 and the contact made by the engagement of said-ar1n50 with said contact spring 52 completes ashort circuit of the holding magnet 30. This causes the deenergizing of the holding'magnet 30 andp'ermits the armature 34 thereof to drop back The contact spring 54 remains in contact with thearm37 untilit comes into engagement with the insulating pin 55. The relation of the arm 50 with respect to said pin is such however that the spring 54 is stopped before it makes contactwith the spring 52 and as the spring 54 is in the bell circuit there will be no signal sounded w'henthearm 50 and the spring 52 are in engagement. If; however, the arm 51 is the one brought into contact with the spring 52 as shown in Fig. 3 the relation of the parts will be changed; In this position of the parts the engagement of the arm 51 with the spring-52will completethe shortcircuito l the holding magnet 80. as in the former case but the arm 51' being longer than the arm 50the contact springwill be held in a position beyond the outer end ottlie insulatingpin 55so that as the spring'fidfollows thearm 37 forward upon therelease of'the holding magnet armature 34 said springti l will be brought into contact withthe spring 52 anda circuit will be completed for a signal60, v

In the equipment of a system embodying the features of this invention the selectors will be arranged in groups each group comprising, say for example, three selectors arms 50 arranged so that they will be brought into engagement with the corresponding contact springs in response to the same number of impulses sent over the line but no two groups will have the parts 50 and 52 in contact at the same time. The separate selectors of each group will be so arranged that a different number of impulses will be required to bring the arm 51 into engagement with the contact 52in the case of each selector although the same number of impulses may be used for bringing the arm 51' and spring 52 into engagement in one selector in each group. This arrangement may be better described by following the operation of the system with reference to Fig. 1.

Assuming in this case that the selectors of group A are adapted to have their arms 50 brought into engagement with the corresponding springs 52 by six'current impulses over the line and the selector C of this particular group is arranged to have its arm 51 brought into engagement with the spring 54 in response to four impulses over the line. Now inorder to operate the signal controlled by selector C of group A the despatoher starts an impulse transmitter which will first send six current impulses over the line. These six impulses will cause all of the selectors on the line to advance their ratchet wheels 32 six steps bringing the arms 50 of all of the selectors in group A into contact with their corresponding contact springs 52 and establishing a low resistance path around the several holding magnets 30 of this group of selectors. This path may be traced for selector C of group A from point 61 of conductor 62 through conductor 63, arm 50, contact spring 52 and conductor 64 to point 65 of a conductor 66. This will put a dead short circuit around the magnet 30 and a corresponding circuit existing at each of the other selectors in group A the holding magnets of all of the selectors in this group will have their armatures retracted. This will not occur at any of the other groups on the line however, inasmuch as the selectors of group A are the only ones in which the arm 50 is in contact with the spring 52. As battery is kept on the line wires 10 and 11 during the release of the holding magnets the circuit of the stepping magnets 31 will remain intact from line wire 10 through retardation coil 67, conductor 62, conductor 63, arm 50, contact spring 52, conductor 64, conductor 66, winding of magnet 31, conductor 68, resistance 69, retardation coil 7 0 and conductor 71 to line wire 11. The current in this path will maintain the magnet 31 energized until the circuit is opened at the despatching station which is the next thing that occurs. This opening however is only momentary andnot'of sufficient durationto permit the release of the holding magnet armatures of any of the other selectors on the line although of sufficient duration topermit the release of the stepping magnet armature. Following this momentary opening there will be four more current impulses sent over the line to which all or the selectors will respond but only one of which, namely selec tor C of group A will have its arm 51 brought into engagement with the contact spring 52. Current will now be held on the line ,wires for a definite length oftirne and the'holding magnet 30'of selectorC of group-A will be again short circuited in the same manner as above described and its armature released. The longer arm 51 now'being the one in engagement with the contact'spring 52 the release of the armature 34 will cause the contact spring 54 to engage contact spring 52 and a circuit will be completed for the signal 60 which may be traced as follows: from one side of battery 72, over conductor 7 3, conductor 63, arm 51, contact springs 52 and 54, conductor? 4, armature of hell 60, contact 75 thereof, conductor 76, winding of bell magnet 60,and conductor 7 7 to the other side'of the battery 72. The op ening of the line'circuit will'release the armature 35 of the stepping magnet 31 which fall'- ing back will carry the spring 54 out of engagement with the spring 52 and at the same time permit the ratchet wheel 32 to return to normal position under action, the spring 33 thus opening the bell "circuit at' two points. r

In the same way if it is desired'to signal any other station on the line the number of impulses necessary to close the releasing contact for that particular group of selectors will first besent over the line and then the number of impulses necessary to close the signaling contact of the particular selector in that group.

The selectors are preferably arranged so that the smallest number of impulses neces sary to releaseany particular group of selectors-is greater than the greatest number of-impulses required to close the signaling contact of any particular selector in. the group; thus it there are five selectors ineach groupthe lowest number of impulses necessary to close the releasingcontacts' should be six, while the'numberof impulses to close the signaling circuit-of an individual selector in the released group may be one, two, three,"four or five. This insures that the arms 51 ofall of the selectors will always be carried past the position at which they will engage the contact spring 52, thus insuring against confusion of signals and providing a simple code arrangement for signaling.

While it may happen that the total number h group B, the circuit will be as follows: from conductor 10 through retardationcoil 6 7, conductor 62, conductor 63, arm 51, contact springs 52 and 54;, conductor 7 4, contact 7 5 of the armature of the bell 60, conductor 76,

winding of bell magnet 60, conductor 80 to point 81 of conductor 68, and thence through resistance 69, retardation coil and conductor 71 to line conductor 11.

I claim 1. In a selective signaling system in combination line wires, aplurality, of selectors connected therewith, impulse sending mechanism for adv ncing all of said selectors simultaneously, and a normally open shunt circuit associated with each selector closed under, the] joint control of said impulse sending mechanism and said selectors and cooperatingtherewith for releasing said selectors at a predetermined position of their movement.

In a selectivesignaling system in com binationline wires, a plurality of selectors connected therewith and arranged in groups, alocal signal associated with each of said selectors, impulse mechanism for advanc-l ing all of said selectors simultaneously and means under the jointcontrol of said impulse mechanism and said selectors for causing thereleasc of selected groups of said selectors and subsequently operating the local signal associatedwith a particular selector of the releasedgroup.

a 3.- In a selectivesignaling system in combination linewires, having a sending station and a plurality of Waystations connected therewith, impulse sending mechanism 'located at said sending station, a selector located at each of said way stations and a localsignal association with each of said selectors, said selectors being arranged in groups, each group being, adapted to have its selectors released and returnedto normal position in response to a predetermined combination of current impulses and each selector adapted to close acircuit for its local signal in response toacombination of current impulses difieringfrom that required to release any particular group.

4:. In a selective l signaling system the combination with line wires, of: selectors connected therewith,eachot said selectors embracingnn electromagnet, impulse sending mechanism for advancing all of said selectors simultaneously, means for reducing the current flow through said elcctromagnet to cause the release thereof, contacts closed by the selectors for controlling said means, said contacts being ,so arranged that they are closed at diiierent groups of selectors in response to different numbers of impulses, the contacts of all of the selectors in one group being closed in response to the same number of impulses, a signaling circuit for eachot said selectors and contacts for said signalingcircuits closed at the different selectors in each group in response to a different number of impulses.

5. In combination With a sending station and a. Way station, impulse transmitting apparatus at said sending station, a step-by step device at said iva y station, contact arms carried by said step-by-step' device, electromagnetically controlled stepping means and holding means for advancingsaid stepby-step device in response to current impulses from said sending station, means tending to return said step-by-step device to normal position, means under the joint control of said impulse sending means, one

of said contact arms and said electromagnetically controlled means and. cooperating therewith for releasing said step-by step device and under the joint control of said impulse sending means and another of said contactarms for subsequently releasing said holding means, and a signaling circuit controlled by said subsequent release of said holding means.

H6. The combination With a sending station and a Way station, of impulse transmitting apparatus at said sending station, a circuit closing Wheel at said Way station,

steppingcand holding magnets for advancing said circuit closing Wheel, means :Eor returning said circuit closing Wheel to normal. position, means for disabling said holding magnet controlled in two separate positions of said circuitclosing wheel, and a signaling circuit closed by the release of said holding magnet in one of the positions oi said circuit closing wheel.

7. In combination with line Wires, a sendiug station and a way station connected therewith, a source of current at said sending station, transmitting apparatus at said sending stationi'ior connectingv said source of current with and disconnecting it from said line wires for predetermined intervals, a selective device at said Way station comprising a step by step circuit closing device and'steppingand holding magnets operating in response to current impulses from the sending station to advance said circuit closing device, a disabling circuit for said llOlCl'? ing magnet, contacts controlled-by the ad vancement of said circuit closing device for closingsaid disabling circuit, and a signaling circuit, the closure of said contacts in releasing said holding magnet and closing response to a predetermined combination of said signaling circuit. 10 current impulses from said sending station In witnesswhereof I hereunto subscribe establishing said disabling circuit for remy name this 23rd day of June, A. D. 1911.

leasing said holding magnet and returning JOSEPH C. FIELD. said device to normal posltion and in re- Witnesses: sponse to a different combination of 1m- FRANK A. FLEIsoHMAN,

pulses establishing said disabling circuit for MORGAN WAsHBURN, J r. 

